As of yesterday evening, Elon Musk already commented on this. Quote: "Battery "breakthroughs" need to state power *and* energy density (not the same thing), plus how long they last. They usually fail on energy. Unquote.

The aluminum-ion cell isn't perfect (yet) as it can only produce about 2 volts, far less than the 3.6V that lithium-ion an muster. Plus aluminum cells only carry 40 watts of electricity per kilogram compared to lithium's 100 to 206 W/kg power density.

The aluminum-ion cell isn't perfect (yet) as it can only produce about 2 volts, far less than the 3.6V that lithium-ion an muster. Plus aluminum cells only carry 40 watts of electricity per kilogram compared to lithium's 100 to 206 W/kg power density.

Click to expand...

Tesla/Panasonic cells are at the 250Wh/kg level.

General note, we now have three different threads discussing this same chemistry, I think all new unproven battery announcments should just get dumped into the "Batteries Stupid" thread until such time as a battery warrants more than a few lines of discussion.

The Al battery pouch cell is mechanically bendable and foldable (Supplementary Video 1) owing to the flexibility of the electrode and separator materials. Further, we drilled through Al battery pouch cells during battery operation and observed no safety hazard, owing to the lack of flammability of the ionic liquid electrolyte in air (see Supplementary Video 2).

An ultrafast rechargeable aluminium-ion battery

Nature 520, 324–328 (16 April 2015) doi:10.1038/nature14340We have developed a new Al-ion battery using novel graphitic cathode materials with a stable cycling life up to 7,500 charge/discharge cycles without decay at ultrahigh current densities. The present Al/graphite battery can afford an energy density of ~40 W h kg[SUP]–1[/SUP] (comparable to lead–acid and Ni–MH batteries, with room for improvement by optimizing the graphitic electrodes and by developing other novel cathode materials) and a high power density, up to 3,000 W kg[SUP]–1[/SUP](similar to supercapacitors). We note that the energy/power densities were calculated on the basis of the measured ~65 mA h g[SUP]–1[/SUP] cathode capacity and the mass of active materials in electrodes and electrolyte. Such rechargeable Al ion batteries have the potential to be cost effective and safe, and to have high power density.

A phone battery has a capacity of c.a. 1800mAh at 3.7V (~6.7Wh). Charging this in one minute would require a current of ~81 amps from the 5V USB port. Not going to happen w/out superconductors and massive advances in small-scale power electronic components.

Every time I see these new "ultra-fast" charge batteries I wonder if they actually have consulted real engineers to see if these batteries could actually be used at the claimed rates.